Reception Equipment - COFDM Downlink System
Navtech offers a wide range of systems to meet all requirements for receiving digital COFDM video transmissions from aircraft. This covers portable equipment, mobile command vehicle systems and fixed site, long range installations. Equipment can be tailored and customised to suit a particular user’s individual requirements.
For reception of video images from ranges up to 60 miles, a fixed array of six sector antennas is used. Typically these have a gain of between 15 and 17 dB (depending on frequency band used). The antennas can be roof-top or mast mounted together with their individual frequency ‘block down converters’ (BDC’s).
These BDCs convert the high frequency transmitted signals to lower frequency UHF signals that are then supplied, via simple co-axial cables, to the receiver. The receiver can thus be mounted in an equipment room several hundred meters from the antennas.
The receiver utilises the latest maximal ratio diversity combining technology for optimal COFDM performance whilst maintaining full DVB-T compliance.
Navtech offers a wide range of systems to meet all requirements for receiving digital COFDM video transmissions from aircraft. This covers portable equipment, mobile command vehicle systems and fixed site, long range installations. Equipment can be tailored and customised to suit a particular user’s individual requirements.
For reception of video images from ranges up to 60 miles, a fixed array of six sector antennas is used. Typically these have a gain of between 15 and 17 dB (depending on frequency band used). The antennas can be roof-top or mast mounted together with their individual frequency ‘block down converters’ (BDC’s).
These BDCs convert the high frequency transmitted signals to lower frequency UHF signals that are then supplied, via simple co-axial cables, to the receiver. The receiver can thus be mounted in an equipment room several hundred meters from the antennas.
The receiver utilises the latest maximal ratio diversity combining technology for optimal COFDM performance whilst maintaining full DVB-T compliance.
6W MRC diversity COFDM receiver
3RU 19” or desk-top mount
Integral touch screen display for
control and monitoring
17dBi sector antenna
N-type connection
Suitable for permanent outdoor installation
For local reception of down-linked video images, the same high performance diversity reception technology that is utilised in the long range system is packaged into a simplified, small lightweight unit. Instead of six high gain sector antennas, two lower gain omni-directional antennas are used (although a high gain antenna can be attached for increased reception range). When operating in high multi-path environments (such as urban areas), particularly when the transmission source or receiver is mobile, the capabilities of diversity reception enable maximum performance and solid, reliable video reception. This 2-way diversity receiver is offered in a variety of packages to suit different applications.
Examples of typical configurations are illustrated below:
‘’ portable receiver
Battery, DC and Mains operation
Optional detachable monitor
‘’ receiver
Optional Integrated LCD monitor
DC and Mains operation
|
